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Chemical Research in Chinese Universities 2001年第1期17卷 31-40页

作者： yin Chun sheng GUO wei min LIU wei ZHAO wei PAN Zhong xiao Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026P.R.China

The molecular structures of hydrocarbons in straight run gasoline were numerically coded. The nonlinear quantitative relationship(QSRR) between gas chromatography(GC) retention indices of the hydrocarbons and their molecular structures were established by using an error back propagation(BP) algorithm. The GC retention indices of 150 hydrocarbons were then predicted by removing 15 compounds(as a test set) and using the 135 remained molecules as a calibration set. Through this procedure, all the compounds in the whole data set were then predicted in groups of 15 compounds. The results obtained by BP with the correlation coefficient and the standard deviation 0 993 4 and 16 54, are satisfied.

关键词： Structural encoding GC retention index Neural network Error back propagation(BP)

Adaptive Quasi Fixed-Time Orbit Control Around Asteroid with Performance Guarantees

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 89-107页

作者： Renyong Zhang Caisheng wei Zeyang yin Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing100094China School of Aeronautics and Astronautics Central South UniversityChangsha410083China School of Astronautics Northwestern Polytechnical UniversityXi’an710072China

This paper investigates a novel quasi fixed-time orbit tracking control method for spacecraft around an asteroid in the presence of uncertain dynamics and unknown *** quantitatively characterize the transient and steady-state responses of orbit tracking error system,a continuous performance function is devised via using a quartic ***,integrating backstepping control technique and barrier Lyapunov function leads to a quasi fixed-time convergent orbit tracking controller without using any fractional state information and symbolic ***,two groups of illustrative examples are employed to test the effectiveness of the proposed orbit control method.

关键词： Prescribed performance adaptive control orbital control asteroid

The Einstein-Khler Metric on the Third Cartan-Hartogs Domain

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Acta Mathematica Sinica,English Series 2008年第10期24卷 1703-1712页

作者： Wen Juan ZHANG wei Ping yin Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China Department of Mathematics Capital Normal University Beijing 100037 P. R. China

In this paper we discuss the Einstein-Kahler metric on the third Cartan-Hartogs domain Y111（n, q; K）. Firstly we get the complete Einstein Kahler metric with explicit form on Y111（n, q; K） in the case of K=q/2 ＋ 1/q-1. Secondly we obtain the holomorphic sectional curvature under this metric and get the sharp estimate for this holomorphic curvature. Finally we prove that the complete Einstein-Kahler metric is equivalent to the Bergman metric on Y111（n, q; K） in case of K=q/2＋1/q-1.

关键词： Einstein Kahler metric holomorphic sectional curvature holomorphic automorphism group

Hydrogen storage properties of as-cast and annealed low-Co La1.8Ti0.2MgNi8.9Co0.1 alloys

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Rare Metals 2016年第7期35卷 559-565页

作者： wei-Qing Jiang Jin Guo Zheng-Cheng Zhou yin-Yan wei College of Physics Science and Technology GuangxiUniversityNanning 530004China School of Basic Medical Sciences Youjiang Medical Universityfor NationalitiesBaise 533000China

Low-Co Lal.8Ti0.2MgNi8.9Co0.1 alloys were prepared by magnetic levitation melting followed by annealing treatment. The effect of annealing on the hydrogen storage properties of the alloys was investigated systematically by X-ray diffraction （XRD）, pressure-com- position isotherm （PCI）, and electrochemical measure- ments. The results show that all samples contain LaNi5 and LaMg2Ni9 phases. LaCo5 phase appears at 1,000 ℃. The enthalpy change of all hydrides is close to -30.6 ***1-1 H2 of LaNi5 compound. Annealing not only increases hydrogen capacity and improves cycling stability but also decreases plateau pressure at 800 and 900 ℃. After annealing, the contraction of cell volume and the increase of hydride stability cause the high rate dischargeability to reduce slightly. The optimum alloy is found to be one annealed at 900 ℃, with its hydrogen capacity reaching up to 1.53 wt%, and discharge capacity remaining 225.1 mAh·g-1 after 140 charge-discharge cycles.

关键词： La-Mg-Ni-based alloy Annealing treatment Hydrogen storage Electrochemical characterization

Adsorption behavior of Zr(IV) and Hf(IV) on a silica-based macroporous TODGA adsorbent

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Nuclear Science and Techniques 2013年第4期24卷 9-16页

作者： yin Xiangbiao wei Yuezhou ZU Jianhua School of Nuclear Science and Engineering Shanghai Jiao Tong University

In order to separate Zr(IV) and Hf(IV) in acidic solution,several kinds of silica-based macroporous adsorbents were *** adsorption selectivity for Zr(IV) and Hf(IV) in HCl solution was investigated,and the TODGA adsorbent for the two elements had the largest adsorption *** effects of acid type,HCl concentration,and temperature on the adsorption behavior of Zr(IV) and Hf(IV) onto the TODGA adsorbent were conducted by batch *** was found that H+exhibited a quite strong influence on adsorption capacity of Zr(IV) and Hf(IV).Isotherm fitting showed that the Langmuir model agrees well with the experimental *** thermodynamic parameters indicate that the adsorption processes for both elements are endothermic *** TODGA adsorbent had the higher adsorption selectivity for Zr(IV) over Hf(IV) and could be promising for their mutual separation.

关键词：大孔吸附剂吸附行为二氧化硅 Langmuir模型锆吸附选择性铪实验数据

Rhodium^Ⅲ/Silver^ⅠRelay Catalyzed C-H Aminomethylation with Imine Equivalents and Lewis Acid Catalyzed[4+2]Cycloaddition of Indoles with Triarylhexahydrotriazine

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Chinese Journal of Chemistry 2020年第9期38卷 947-951页

作者： Ruixing Liu yin wei Min Shi State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisUniversity of Chinese Academy of ScienceShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Summary of main observation and conclusion A Rh^Ⅲ/Ag^Ⅰrelay-catalyzed C(sp^2)—H coupling of indoles with triarylhexahydrotriazine(THT)is reported in this *** merging Rh^Ⅲ-catalyzed C(sp^2)—H bond activation and silver promoted THT dissociation,an efficient indole's C3 aminomethylation protocol is uncovered,providing C3 aminomethyl indoles in good yields and exhibiting potential applications for the synthesis of complicated bioactive *** revealed the C3-selectivity of this reaction through a detailed mechanistic ***,during the examination of the reaction conditions,we discovered another[4+2]cycloaddition pathway to afford tetrahydro-indolo[3,2-c]quinoline scaffold products via silver or Lewis acid catalysis.

关键词： silver catalyzed conclusion

Operational Control of Low-voltage MTDC Systems in a Cyber-physical Environment

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1569-1582页

作者： wei Deng wei Pei Ningning Li Xue Zhang yin Yi Li Kong Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication Engineering(EECE)University of Chinese Academy of SciencesBeijing 100049China

Based on the standardized cyber-physical modeling and communication system-IEC 61850,this paper establishes the operational control architecture of a low-voltage multi-terminal DC(LV-MTDC)*** coordinated operational control strategies,including power electronic transformer(PET),and voltage source converter(VSC),are *** a cyberphysical model of the system based on IEC 61850 is built,according to the application requirements of operational control in the LV-MTDC *** this basis,the implementation method of system operational control based on IEC 61850 is proposed,including the software/hardware design of the intelligent electronic device(IED),dispatching operations and uninterrupted power *** simulation environment is further built to verify the system operational control technology,and the test platform is used to carry out the actual *** research results show that the operational control technology for the LV-MTDC system proposed in this paper is feasible,which can guarantee the rapid and accurate information exchange of control commands and settings,and thus effectively realize the operational control of the LV-MTDC system under complex conditions.

关键词： Cyber-physical system distributed energy resources IEC 61850 intelligent electronic device low-voltage multi-terminal DC system

Landslide Developmental Characteristics and Response to Climate Change since the Last Glacial in the Upper Reaches of the Yellow River, NE Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 635-646页

作者： yin Zhiqiang QIN Xiaoguang yin Yueping ZHAO Wuji wei Gang Institute of Geology and Geophysics Chinese Academy of Sciences China Institute of Geo-environment Monitoring China University of Geosciences (Beijing) Qinghai Environmental Geological Prospecting Bureau

The upper reaches of the Yellow River in northeastern Tibetan Plateau are geohazards *** evolution of the Yellow River,chronology of some landslides,and spatiotemporal distribution characteristics of super large scale and giant landslides within the region are summarized using paleoclimate evidence,and the relationship between the intensive landslide period and climatic changes since the Last Glacial period is *** is concluded that （1） Super large scale and giant landslides are distributed widely within the region,particularly in the Qunke-Jianzha basin.（2） The chronological sequence of landslides is established by dating the slip zones of landslides and analyzing the relations between landslides and their overlying or underlying loess *** landslide development periods are determined：53-49 ka BP,33-24 ka BP,10-8 ka BP,5-3.5 ka BP,and the present.（3） These correspond closely to warm and wet periods during the last 100,000 years,i.e.,two weak paleosol development stages of Malan loess deposited during the last Glacial period in the Chinese loess Plateau,L1-4 and L1-2 that belong to the marine oxygen isotope stage 3,the last deglaeial period,the Holocene Optimum,and the modern global warming period.（4） Landslide triggers may be closely linked to warm and wet periods related to rapid climatic transitions.

关键词： landslide developmental characteristics climate change upper reaches of the Yellow River response

Microstructural stability of 9-12%Cr ferrite/martensite heat-resistant steels

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Frontiers of Materials Science 2013年第1期7卷 1-27页

作者： wei YAN wei WANG Yi-yin SHAN Ke YANG Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The microstructural evolutions of advanced 9–12%Cr ferrite/martensite heat-resistant steels used for power generation plants are reviewed in this article. Despite of the small differences in chemical compositions, the steels share the same microstructure of the as-tempered martensite. It is the thermal stability of the initial microstructure that matters the creep behavior of these heat-resistant steels. The microstructural evolutions involved in 9–12%Cr ferrite heat-resistant steels are elaborated, including (1) martensitic lath widening, (2) disappearance of prior austenite grain boundary, (3) emergence of subgrains, (4) coarsening of precipitates, and (5) formation of new precipitates, such as Laves-phase and Z-phase. The former three microstructural evolutions could be retarded by properly disposing the latter two. Namely improving the stability of precipitates and optimizing their size distribution can effectively exert the beneficial influence of precipitates on microstructures. In this sense, the microstructural stability of the tempered martensite is in fact the stability of precipitates during the creep. Many attempts have been carried out to improve the microstructural stability of 9–12%Cr steels and several promising heat-resistant steels have been developed.

关键词： heat-resistant steel microstructure martensite precipitate microstructural evolution

Studies on the structure and catalytic performance of Cu-Zn-Al catalyst prepared by liquid-phase preparation technology under different heat treatment atmosphere

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Journal of Natural Gas Chemistry 2010年第6期19卷 611-616页

作者： Zhihua Gao wei Huang Lihua yin Kechang Xie Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 Shanxi China

Cu-Zn-Al slurry catalysts were prepared using a complete liquid-phase preparation technology under different heat treatment *** catalysts were characterized using X-ray diffraction,X-ray photoelectron spectroscope,and N2 *** application in the single-step synthesis of dimethyl ether from syngas was also *** results indicate that the type of heat treatment atmosphere has an influence on the Cu species and the Cu0/Cu＋ ratio on the catalyst ***,the final Cu/Zn ratio on the catalyst surface is mainly dependent on the composition and reaction environment of the catalyst and less on the type of heat treatment *** prepared catalysts can suppress sintering of active sites at high temperatures,and the type of heat treatment atmosphere mainly affects the capability of the catalyst for methanol *** catalysts perform best using N2 as the heat treatment atmosphere.

关键词： liquid-phase preparation technology slurry reactor dimethyl ether syngas heat treatment atmosphere